The multi-disciplinary program describes in this application produces scientists having a base knowledge in environmental toxicology coupled with research expertise gained in a departmentally-based graduated program. Predoctoral trainees must meet the full Ph.D. requirements of their "home" department and complete the coursework, research and interactive aspects of the Multi-disciplinary Ph.D. Program in Environmental Toxicology administered by the Institute for Environmental Toxicology (IET). The degree awarded recognizes the dual nature of the training by listing the department-environmental toxicology (e.g., Ph.D. in Biochemistry-Environmental Toxicology), Graduates of the program are well-equipped to conduct research and interact with other scientists in the course of solving complex environmental problems that require collaborative, multi-disciplinary approaches. Fifteen training faculty conduct predoctoral training in four departmental Ph.D. programs (Pharmacology and Toxicology, Biochemistry, Food Science and Human Nutrition, Zoology). Added to the department- based education and environmental toxicology research training in departments as didactic, toxicology-oriented courses required by the Multi-disciplinary Ph.D. Program in Environmental Toxicology. This coursework and less formal multi-disciplinary interactions and activities provided by the IET imparts a wider scope of knowledge than is available within individual departmental programs. Research topics for trainees are available in mechanisms-related toxicology encompassing: organ systems (e.g., hepatic, immune, endocrine, neuronal, respiratory), carcinogenesis, reproduction and food safety. In addition, research training is available on modern analytical techniques used to identify and quantitate toxic responses. Postdoctoral trainees conduct research in the laboratory of one (or more) of the training faculty and gain additional environment toxicology experience through participation in IET activities and courses. This application is for support of six predoctoral and three postdoctoral trainees, thereby continuing a highly effective multi- disciplinary training program which mixes traditional and non- traditional approaches to prepare graduates to make significant contributions to the field of environmental toxicology.